Planooraph co



c. G. BAUER'.

COMPOUND AR PUMP.

APPLICATION HLED JUNE l, 1917.

Patented July 1, 1919.

THE COLUMBIA PLAOGRAPH C0., WASHINTON. b. c.

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` .1 cHARLEs e. Bauen, or BROOKLYN, `New YORK.

coi/POUND Ara-PUMP.

T0 all fio/tom t may concern:

Be it known that I, CHARLES G. Bauen,

a citizen of the United States, residing at useful Improvements in Compound Air- Pumps; and 1 do hereby declare the following to be a full, clear, and eXactdescription of the invention, such as will enableothers skilled in the art to which it appertains to make and use the same.

My present invention relates to an .improvement in compound air pumps such as are used for inflating pneumatic tires and the like, and provides a cheap and simple construction whereby the base is made far more durable than heretofore as well as lighter and more sightly.

In pumps of this kind as heretofore made, the bottoms of the high and low pressure cylinders have been screwed from above into appropriate openings in a heavy cast iron base, and it has been necessary to bore slanting openings for passage of air through the material separating the two chambers `in the base which receive the cylinders. These bases, besides being more or less unsightly, are quite heavy, and are easily broken when the pump is dropped or is accidentally struck. rllhey are also likely to leak if great care is not exercised in assembling.

It has long been deemed desirable to provide some construction suited to the use of sheet metal, preferably steel, in the making of these bases. terial offers the advantage of superior lightness, takes up less room and is practically unbreakable. My invention covers a structure which solves this problem in a practical manner and with economy of labor and material. My improved pump also comprises certain novel features in connection with the finishing of the upper end of the high pressure cylinder which are hereinafter' described.

My improved pump is illustrated in a preferred form in the accompanying drawings, wherein Figure 1` is an elevation of the pump with parts shown in vertical section, Fig. 2 is a bottom plan view of the same, and Fig. 3 is a horizontal sectional view showing the tops of the cylinders in plan.

lThe usual high and low pressure cylinders used in pumps of this kind are shown at 10 and 11, respectively, and the two piston rods Specificaticn of Letters Patent.

1t is evident that this ma- 12 and 13 are joined at usualcommon handle 111.

Myimproved base, forjoining the cylin- 20, and is made to fit the depression 17 in the preferred` form, although it is not, of course, essential to the invention that any depression should be provided in this con-- nection. This plate 20 is also provided with a recessed part 21, stamped into appropriate form in a well known manner.

In assembling the pump, the straight plain tubes l() and 11 designed to act as cylinders are passed up through the cylindrical portions 18 and 19, until the slightly fiaring lower ends of said tubes fit snugly against the interior surfaces of said openings. The tubes are then securely joined to the y. plate 15 in this position by the sweating process, thus providing a very strong joint, and one `that is entirely and permanently air tight. The second or closing plate 20 'is then fitted to its seat and is sweated in place. In thisposition the depression or recess 21 affords ample room for free passage of air from lone cylinder to the other.

e Patented July 1, 1919. Application med :rune 1,1917. seriaiuo. 172,177.

their tops the y The closing device for the top or discharge end of the high pressure cylinder comprises three principal portions.

First, the under part of the sheet metal cap, shown at 22, is formed below to screw onto the top of the pipe 1Q and is extended on `one side, as shown in Figs. 1 and 3, to accommodate a suitable opening to receive the usual valve Q3 on the end of the flexible air-delivery pipe 24. The upper surface of this under portion is spun outward to form a horizontal flange 25.

The upper part of the sheet metal cap is shown at 26, and is provided with a peripheral portion having an upper face :27, which is turned at its edge first downward and then inward to fit snugly under the flange 25 on the lower cap. Between the portion 27 of the upper cap and the flange 25 of the lower cap is inserted a flat packing 28, which may be of rubber, fiber, paper or wicking. The whole is strongly compressed in manufacture, and provides a strong and permanently air tight closure.

Over the center of the tube l0, the upper cap is stamped or spun downward to form a packing cup 29, into which is `screwed a closing gland 30 having a polygonal head as shown in Fig. 3 to permit use of a tool in screwing it home. lThe usual packing is placed beneath the gland, and there is thereby formed an air tight packing for the piston rod 12,.

In order firmly to unite the two cylinder?J 10 and l1 at Atheir upper ends, the air tight cap 31 on the cylinder 11 is furnishedjvith an ear 32 of sheet metal which extends over the top of the cap portion 26, and is provided with an opening through which passes the gland 30. The ear 32 is thus ,secured under the flange at the topl of the gland.

It will be seen that my improved nonbreakable base is so constructed as to afiord ample room for passage of air from one cylinder to the other, while taking up much less room than the old cast iron base, and affording a more reliable and durable airtight construction.

What I claim is- In a pump of the class described, a closing cap for the high pressure cylinder comprising a lower portion itting said cylinder and having an extension for receiving the valved end of the delivery pipe, said portion having a horizontal flange supporting a packing; in

combination with an upper portion provided with a packing gland and having its periphery turned first downward and then inward and compressed under the flange and packing of the lower cap portion.

In testimony whereof, I affix my signature.

CHARLES G. BAUER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

